Improvement



GEORGE V. BROIVN, OF ASHBURNHAM, MASSACHUSETTS,

IMPROVEMENT IN SCREENS.

Specification forming part of Letters Patent No. 162,95, dated May 4,1575; application filed April 7, 1874.

To all whom it may concern:

Be it known that I, GEORGE IV. BROWN, of Ashburnham, in the county ofWorcester and State of Massachusetts, have invented an Improved Screen;and I do hereby declare that the following, taken in connection with thedrawings which accompany and form part of this specification, is adescription of my invention sufficient to enable those Skilled in theart to practice it.

The invention relates to the construction of a screening mechanism forsifting buildingsand. In my invention I use a plain rectangular screenwith close sides, and closed at one end and open at the other; and thisscreen I place in or upon a frame, in which the front end of the screenis supported upon a stationary bar, or in stationary bearings, withprovision for keeping the screen from moving eudwise, but permitting thescreen to rock slightly upon the support, the opposite end of the screenhaving a journal or pin that extends through a vertical slot at theopposite end of the frame, and rests upon. a cam or wiper wheel,connected to or furnishing part of a hand driven wheel, the screen beinginclined, and the upper end being intermittently raised by the cam-wheeland falling by grav ity. The invention consists, primarily, in theconstruction or arrangement thus generally described.

The drawing represents a machine embodying the invention.

Figure 1 shows the machine in plan. Fi 2 is a rearend elevation of it.Fig. 3 is a sectional elevation.

(t denotes the frame, and b the screen. The bottom board 0 at the mouthof the screen is shown as grooved beneath, as seen at d, and as restingupon a cross-bar, e, that sets into the groove, the bar and groovekeeping the front end of the screen in place. At the rear end of theframe is a verticallbar, f, having a slot, g, through which extends ajournal or pin, h, projecting from the head of the screen. The end ofthis journal carries a roll, t", resting upon a cam or wiper wheel, is,turning upon a pin, l, extending from the frame, this wheel being fixedto or forming part of a wheel that may be operated by a handle, on.

As the wheel is turned the head of the screen is alternately raised bythe wheel and dropped by gravity, and by the conc'nssive movement thesand thrown upon the inclined screen is rapidly sifted, the gravelrunning down the screen, and being discharged at its mouth. WVhen thescreen falls, it drops preferably upon a spring or cushion, 00, underwhich cushion is a set-screw, regulating the rise and fall of thescreen.

In sitting, and especially when the sand is damp, the square mesh of thescreen is liable at first to be clogged, and I have found that by havinglong openings in the mesh toward the head of the screen this dispositionto clog is overcome. To obtain these long openings the wire-cloth mustbe woven with them; or they may be form ed by removing every thirdtransverse wire. The removal of every other wire would destroy the Web.

I construct a hopper, 0, having journals 1? at one end, resting instationary bearings q, this hopper having an adjustable gate, 1', at itsopposite end, and an inclined bottom, 8, ieading thereto. The hopper atthe foot of the incline rests on the frame of the screen 7), near theintermittently rising and falling end thereof, and partakes of thejarring movement of the screen, so as to jar the sand in the hopper,causing it to move down the incline and escape under the gate, and fromthe hopper into the screen. The gate is adjusted in height to deliverthe sand as fast as is desirable, and the sand falls in one place uponthe screen, and is uniformly sifted before it reaches the mouth of thescreen.

The frame and screen thus made may be advantageously used either at thesand-pit or where the sand is to be used, the hopper being especiallyintended for use at the building to screen sand for fine finish.

The frame for the screen may be a cart-bod y, recesses being made in theupper edges of the side board, near the foot-board, for supporting theopen end of the screen, and a slotted post or bar being fastened to thehead-board to receive the journal and the shaft of the camwheel 70.

This screen is not only intended for screening sand, but may be used forcoal and any other screenable substance to which itcan be applied.

I claimand guided by vertically-slotted bars, and car- In a screen inwhich a hopper rests at one rying a roll that rests upon a cam or wiperend upon, and is shaken by the movements of, wheel, substantially asshown and described. the screen, the arrangement of the screen in-Executed this 4th day of March, A. D. 1874.

clined in a direction the reverse of that of the GEORGE W. BROWN.hopper, the lower end of the latter resting on Witnesses: 1

the intermittingly rising and falling end of the NEWTON HAYDEN,

screen, which has ajonrnal extending through 0. K. WOOD.

